White Spruce Biochar for Point-of-Use Drinking Water Treatment

Abstract:

Small systems regularly struggle to produce treated drinking water compliant with the health standards established by the USEPA thus prompting an obvious need for appropriate innovative treatment solutions. Of these potential solutions, point-of-use treatment devices designed to effectively reduce chemical contaminants in residences using inexpensive, replaceable sorbent materials may be best suited.

Our current USEPA-funded project focuses on the production, performance and introduced application of a locally produced Alaskan biochar intended for use as an alternative sorbent media in point-of-use filtration technology. Conducted through the University of Alaska Anchorage, this research effort attempts to develop our value-added biochar product into a sustainable, single-media sorbent capable of removing multiple contaminants from groundwater sources. In this study, the sorptive efficiencies of White Spruce biochar for regulated organic (TOC) and inorganic (As, Cl₂, F^-) contaminants are experimentally evaluated using dynamic, small scale column testing.

To achieve optimal understanding of White Spruce biochar sorption and identify the most effective type of sorbent material, a wide array of production technologies and processing conditions were conducted. Lower conversion temperatures (450-550 ^oC) were achieved in the laboratory in the absence of oxygen using a manufactured pyrolysis unit while higher temperature ranges (800-1000^oC) were achieved in field environments using a custom-built, low oxygen gasification system. Differences in production technologies and corresponding temperature ranges may impact biochar compositions and subsequent surface areas and possibly influence each material’s ability to effectively sorb targeted contaminants.

Small scale column testing was chosen for this project due to its convenience as a bench-scale technology and scalability to point-of-use devices. The results of this project will reveal the practicality of using this low-cost, sustainable sorbent in small-scale, point-of-use applications and ultimately establish any evidence for this product’s undiscovered placement in innovative treatment solutions. This poster will present our biochar production and characterization methodology and treatment efficacy results.